A screen displayed in a monitor (display) of the computer or the like is displayed in a browser such as Internet Explorer (IE: trademark) or Firefox (trademark), for example, and is operated with software such as Windows (trademark) OS, iOS (trademark), or Android (trademark). There is also provided a system for displaying an image taken by a WEB camera or the like on a monitor of a computer or the like.
Conventionally, such monitoring of a person or an object using an image of a monitoring target displayed on a monitor of a computer or the like requires a person constantly watching the image.
Patent Document 1 proposes one example of a monitoring device employing a camera. Specifically, to image data taken by imaging means, a landscape-oriented rectangular specific area parallel to a transversal plane of a frame image is set by specific area setting means, image data of the specific area is taken out by image data processing means for each of a plurality of frame images, and a motion vector is extracted from the taken out image data. In addition, change detecting means determines that it is dangerous as another mobile object is too close to own mobile object when a value obtained by addition of a vector value in a predetermined direction in motion vector information is greater than a threshold that has been set by change detection threshold setting means, and notifies a driver of the danger by alerting sound and alerting display via change notifying means.